<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>数组反转</title>
</head>

<body>
  <script>
    let arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
    for (let i = 0; i < arr.length/2; i++) {
      let temp = arr[i]
      arr[i] = arr[arr.length-1-i]
      arr[arr.length-1-i] = temp
    }
    console.log(arr);
    
  </script>
</body>

</html>